"ATO HQ warns that in case of continued shelling on Ukrainian positions after 4:30 p.m., ATO forces will have to open response fire in order to avoid losses among military personnel," the message says.

It is noted that the Joint Coordination Center for Ceasefire Monitoring was informed about such decision already.

ATO HQ explained that separatists are attacking Ukrainian positions along demarcation line all day using rocket launchers, heavy machine guns, small arms and weapons banned by Minsk agreement.